Generally, the grilling devices comprise an upper shell and a lower shell, a upper pan disposed on the lower surface of the upper pan and a lower pan disposed on the top surface of the lower shell. The grilling usually are used for cooking food with much oil such as meat, much oil will be produced in cooking, and the oil must be discharged from the pan timely, or else the oil will affect the taste of the cooked food. Commonly, an oil discharging opening is set in the front side of the pan of the grilling device, and an oil box is disposed under the pan for collecting the oil. Pans of the grilling device are plane or a little slant, thus the oil can flow into the oil box.
However, the above grilling device have the following disadvantages: firstly, because the pan is plane, the oil discharge speed is slow and the oil is stayed in the grilling device for too long, thus affect the taste of the cooked food; secondly, in cooking, the steam may be discharged from the front side, thus the users may be burned by the steam; thirdly, a plane pan has smaller cooking surface in same size of the grilling device.